Developing Algebraic Thinking - Suzanne Alejandre
Teacher lesson plan and student kinesthetic activities on the Traffic Jam activity and applet, as originally published in the inaugural (Fall, 2002) issue of ON-Math, an electronic journal of the National Council of Teachers of Mathematics (NCTM).
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Developing Function Sense with SAQs - Judah Schwartz
A work in progress, this is an online book on the philosophy of teaching functions in middle and high school algebra. He has come to believe "that approaching algebra through the study of functions using symbolic and graphical representations simultaneously
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A Dictionary of Units - Cleave Books
A summary of units of measurement world-wide (current units and a few of historical interest); conversion factors to the SI (Systeme International); an outline of the SI; its basic defining standards and some of its derived units; all the SI prefixes
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Digital Deletions - Pierre Ysewijn
An interactive JavaScript version of Conway's Digital Deletions game, in which numbers in a string are lowered to zero or erased. Users can play with different numbers of digits, different strategy levels, different starters, different sources of digits
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DigitalLesson.com - Mark Tully
Website for middle school math teachers that has middle school math lessons, games, projects and activities for use in the classroom. Free newsletter, other resources for sale.
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Digital Math - Santa Barbara County Education Office
A site to assist Algebra I, Grade 7, and Grade 6 students, their parents, and educators with the California State Mathematics Content Standards. Log in for Quicktime that provides step-by-step instruction to solve problems aligned with the mathematics
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Digital Promise
Improving the opportunity to learn for all Americans, and accelerating innovation in education, through technology and research. Initiatives include Digital Promise Schools, in partnership with Verizon; the League of Innovative Schools; educator micro-credentials,
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The Digit Connection - Lizzie
A tribute to the number pi through music, poetry, and fiction. (Meet Sailor Pi!) Also includes a brief history of pi with some ways to calculate it, a quote collection, and ways to celebrate the number - even if it's not Pi Day.
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DimensionU
Creators of educational software that put the action adventure fun of mainstream video games in a learning environment that prepares students for high stakes exams. First person shooter games Dimenxian, Evolver, and Meltdown contain 3-dimensional virtual
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Discovery and Conjecture - Kim Van Duzer
Blog by a 2nd grade teacher at a public school in Brooklyn, New York. Van Duzer, who co-founded the NYC Math Lab, describes hereslf as "especially interested in teaching math in ways that encourage sensemaking and joy, in creating equitable math communities,
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discretemath - Math Forum
A discussion group for subject matter concerning teaching and researching of discrete mathematics at all levels. It began as a closed list for the researchers and educators who participated in the Rutgers University Discrete Math and Theoretical Computer
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Discrete Math Problem of the Week (PoW) - Math Forum
Discrete math problems from a variety of sources, including textbooks, math contests, NCTM books, and puzzle books, and real-life situations, designed to reflect different levels of difficulty. From 1999 until 2002, this service challenged students with
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Distance Calculator Between Cities - Dan Gallagher
Enter two cities or countries and this CGI illustrates them on a scaled political map, calculates the distance between the two locations in miles and kilometers, and provides information about latitude, longitude, bearing, and airports. All latitude and
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